Documents, not assurances
Both licence and inspection carry dates.
Both documents that permit this work expire. That makes them checkable, which is better than trustworthy.
Agricultural contracting is bought on reputation, which is reasonable but incomplete, because two of the things that decide whether a contractor may lawfully apply crop protection at all are documents with expiry dates on them. The first is a phytolicence. Anyone using, distributing or advising on plant protection products in a professional capacity in Belgium must hold one, in the category corresponding to their role: assistant professional user, professional user and distribution to professionals, or distribution to amateur users. It runs for six years and renews only on completing the prescribed continuing education, which is precisely why the date matters more than the fact. A licence that has lapsed looks identical to one that has not until somebody reads it.
The second is the equipment. Application machinery in professional use must pass a periodic technical inspection, every three years, carried out by the competent service, and carry proof of it; using a machine that has not passed is an offence rather than a lapse. There is a practical reason behind the rule as well as a legal one. A sprayer out of calibration applies a dose nobody intended, and a worn nozzle produces drift that lands where no product authorisation permits it to. Both failures are invisible from the cab and obvious in a buffer zone.
The third point is the one that costs farmers money most quietly, because it is an obligation that cannot be delegated along with the work. The operator of the land remains responsible for the treatment register covering their own parcels: product, dose, date, parcel, crop, kept for at least three years. A contractor who applies something and drives away without handing those details over has left the client in default, and the client usually discovers it at the worst possible time. Handing them over after every pass costs nothing and is simply part of the job. Where a product authorisation sets a condition that conflicts with what would be convenient — a dose, a growth stage, a buffer zone to surface water — the authorisation is the instruction, and we would rather say so before the work than explain it afterwards.
Both licence and inspection carry dates.
Dose, stage and buffer come from it.
The register is the operator's duty.
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